Fireworks propel a cocktail of chemicals into the atmosphere, many of which can harm both people and the environment. The vivid colours in firework displays come from metallic compounds such as barium or aluminium that can have negative impacts on animal and human health. Additionally, to produce the oxygen needed for an explosion, many fireworks contain oxidisers known as perchlorates. These can dissolve in water, contaminating rivers, lakes and drinking water. Finally, fireworks release a fine cloud of smoke and particulate matter, affecting local air quality. Some newer, ‘cleaner’ fireworks replace perchlorates with safer alternatives, or use compressed air to reduce smoke created.

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